Apparatus and method for placing staples in laparoscopic or endoscopic procedures

ABSTRACT

A surgical stapler for placing lateral lines of staples and making an incision, all through an endoscopic tube, includes an anvil member which is mounted to the distal end of an elongated housing. A tubular collar disposed around the arm of the anvil member is movable to a distal position to bias the anvil member and a cartridge assembly into cooperative alignment, thereby clamping body tissue to be fastened between the anvil member and cartridge assembly.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of application Ser. No. 08/129,862 filed Sep. 30,1993, now U.S. Pat. No. 5,413,268; which is a Rule 1.60 continuation ofapplication Ser. No. 08/027,566 filed Mar. 8, 1993, now abandoned; whichwas a Rule 1.62 continuation of application Ser. No. 07/593,654 filedOct. 5, 1990, now abandoned; which was a Rule 1.53 continuation-in-partof application Ser. No. 07/358,646 filed May 26, 1989, now U.S. Pat. No.5,040,715.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to surgical stapling apparatus, and moreparticularly to a surgical stapler for mechanically effecting aplurality of lines of stitching or ligating staples in body tissue.

2. Background of Related Art

In some surgical operations it is necessary to adjoin two hollow bodyorgans alongside each other, generally with their longitudinal axesparallel to each other, and to effect a longitudinal cut through thecontacting circumferential walls of the two organs so that the twoorgans constitute a single hollow chamber along the length of the cut.Correspondingly, the circumferential portions of the two adjoiningorgans on each lateral side of the cut must be sutured by at least oneline of "stitches" in order to maintain the integrity of the union.

Instruments for this purpose can comprise two elongated fingers whichare respectively insertable into each organ from an open end thereof,the two fingers thereby having between them the two adjoining walls ofthe organs. Typically, one of the fingers carries a disposable cartridgehousing a plurality of staples arranged in at least two lateral rowswhile the other finger comprises an anvil for curling the staple legsinto hook form upon their being driven against the anvil. The staplingoperation is effected by a pusher which travels longitudinally along thecartridge carrying finger extending into one organ, with the pusheracting upon the staples to place rows of staples in body tissue.Immediately behind the pusher and laterally positioned between thestaple rows is a knife which severs the facing adjoining walls of thetwo organs to thereby longitudinally open the two organs to each otherbetween the rows of staples.

One such instrument is disclosed in Bobroy et al. (U.S. Pat. No.3,079,606). The instrument disclosed therein comprises an apparatus forsimultaneously making a longitudinal incision and applying a row ofstaples on both sides of the incision. A further improvement isdisclosed in Green (U.S. Pat. No. 3,490,675).

A later development disclosed in Green (U.S. Pat. No. 3,499,591) appliesa double row of staples on each side of the incision. This isaccomplished by a cartridge assembly wherein a cam member moves within aguide path between two sets of staggered staple carrying grooves. Stapledrive members located within the grooves each have two staple pusherplates, and sloping surfaces disposed within the guide path so as to becontacted by the longitudinally moving cam and be driven along thegroove to effect ejection of two staples.

Other instruments use similar structure to mechanically suture anddivide organic tubular structures such as, for example blood vessels.With these instruments, the tubular structure to be sutured and/ordivided is inserted between the jaws of the cartridge, the cartridgejaws close and a pair of pushers advance and suture the organicstructure in two spaced locations with a pair of surgical fasteners.Where dividing is desired, a blade comes forward and divides the tubularstructure at a position intermediate the pair of fasteners. Suchinstruments are shown in U.S. Pat. Nos. 3,740,994 and 3,955,581, thedisclosures of which are incorporated herein by reference.

These above-mentioned instruments comprise upper and lower frames orreplaceable cartridges which must be assembled before use, anddisassembled after use. Such instruments have been used successfully insurgical operations requiring the placement of gastrointestinalanastomosis, and ligating and dividing tubular structures but theyrequire the surgeon to have direct manual access to the operation site.

However, in laparoscopic procedures surgery is performed through a smallincision, and in endoscopic procedures surgery is performed throughnarrow endoscopic tubes inserted through small entrance wounds in theskin. Up to now there have been no instruments for placing lateralstaple lines in laparoscopic or endoscopic procedures. Nor has therebeen any instrument suitable for placing lateral lines of staples andcutting tissue therebetween in laparoscopic or endoscopic procedures.

Because endoscopic procedures are more common than laparoscopicprocedures, the present invention shall be discussed in terms ofendoscopic procedures and apparatus. However, use herein of terms suchas "endoscopic", "endoscopically" and "endoscopic portion", amongothers, should not be construed to limit the present invention to astapling and cutting apparatus for use only in conjunction with anendoscopic tube. To the contrary, it is believed the present inventionmay find use in any procedure where access is limited to a smallincision, including but not limited to laparoscopic procedures. Also, asused herein the terms "fasteners" and "staples" shall be treatedequivalently. Unless otherwise stated, the term "cartridge assembly"shall include at least the cartridge itself and staples or fasteners andstaple drive members disposed therein.

3. Objects of the Invention

Accordingly, it is one object of the present invention to Frovide asurgical stapling apparatus.

It is another object of the present invention to provide a surgicalstapling apparatus which can adjoin hollow body organs alongside eachother.

It is yet a further object of the present invention to provide asurgical stapling apparatus which can be used endoscopically.

Another object of the present invention is to provide a surgicalstapling and cutting apparatus which can be used endoscopically.

It is a further object of the present invention to provide a surgicalstapling apparatus which sutures and divide tubular structureendoscopically.

It is a further object of the present invention to provide a surgicalstapling apparatus having replaceable cartridge assemblies.

Another object of the present invention is to provide a surgicalstapling apparatus with replaceable cartridge assemblies whichdeactivate after firing.

A further object of the present invention is to provide a surgicalstapling apparatus wherein the knife is prevented from making multiplecutting passes through the tissue.

These and further objects and advantages are achieved by providing asurgical stapling apparatus insertable through a small incision ornarrow tube for driving surgical fasteners into body tissue and cuttingthe body tissue between rows of staples.

SUMMARY OF THE INVENTION

In accordance with the present invention a surgical stapling apparatusis provided for placing one or more rows of staples endoscopically.Advantageously, a stapler apparatus constructed in accordance with theinvention may further include a knife for making an incision in bodytissue between rows of staples. The latter configuration may findparticular use in adjoining two hollow organs or in removing an organ,such as the appendix.

Briefly stated, the surgical stapler in accordance with the inventioncomprises:

a) a frame;

b) a tubular portion defining a longitudinal axis and extending distallyfrom said frame, said tubular portion including:

i) an elongated housing having means for removably mounting a cartridgeassembly, said cartridge assembly including a plurality of surgicalfasteners mounted therein, and having a tissue engaging surface;

ii) an anvil member having a fastener forming surface, said anvil membermounted to said elongated housing;

iii) means for effecting relative movement between said cartridgeassembly and said anvil member; and

iv) means for ejecting said surgical fasteners from said cartridgeassembly, whereby said fasteners engage said fastener forming surface.

In one embodiment of the invention the frame and endoscopic portion ofthe instrument are reusable with replaceable staple carrying cartridges.

In another embodiment of the invention the endoscopic portion is formedas a disposable unit detachable from a reusable handle portion includingthe frame.

In yet a further embodiment of the invention, the entire instrument maybe constructed as a single-use, disposable unit.

In a still further embodiment of the invention, the cartridge assemblydisposed on a distal end of the instrument is replaceable after firing.

In another embodiment of the invention, the cartridge assembly containsstructure for ligating and/or dividing tubular structure.

According to the method of the present invention, the endoscopic portionof the apparatus is inserted into the body through a small incision or,more likely, through an endoscopic tube. With the anvil member in theopen position, body tissue is disposed between the anvil member and thetissue engaging surface of the cartridge assembly. The anvil is thenclosed against the cartridge to clamp the body tissue between the anviland cartridge. The instrument is fired so that staples ejected from thecartridge penetrate through the body tissue and are formed closedagainst the anvil. Where appropriate, a knife forms an incision betweenseveral rows of staples. After the instrument has been fired, theclamping action of the anvil and cartridge assembly is released and theendoscopic portion of the instrument is withdrawn from the body.

The present invention advantageously permits a surgeon to performinternal stapling and cutting procedures without full access to thestapling site. Surprisingly, the stapling and cutting instrument inaccordance with the invention may be inserted through a small incisionor tube in order to place multiple staple lines and make an incision inthe stapled tissue between several rows of staples.

The ability to perform stapling and cutting procedures through a smallincision or tube remarkably reduces blood loss, tissue trauma andpatient recovery time, contributing to improved health care practices.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective cutaway view of the invention;

FIG. 2 illustrates an exploded view of the frame;

FIG. 3 illustrates an exploded view of the toggle lever actuating means;

FIG. 4 illustrates an exploded view of the interior actuating means;

FIG. 4A illustrates a sectional side view of the collar pivot holdercollar pivot support, collar pivot wheel, channel pin holder and channelpivot;

FIG. 5 shows the tubular cover;

FIG. 5A illustrates the connection between the cover and thumbwheel;

FIGS. 6 and 7 show the collar shaft and collar;

FIGS. 8 and 9 illustrate the cam bar channel, cam bars, knife and cambar adapter;

FIGS. 10 and 11 illustrate the housing and anvil;

FIG. 11A illustrates a sectional view of the housing and collar;

FIG. 12 illustrates an exploded view of the cartridge, staple drivemember and staples;

FIG. 13 illustrates a side view of the cartridge;

FIG. 14 illustrates the surface of the cartridge which comes in contactwith body tissue;

FIGS. 15A and 15B illustrate the clamping action of the instrument;

FIG. 16 illustrates a three staple drive member that can be used withthe present invention;

FIG. 17 illustrates a sectional view of the endoscopic portion of theinstrument in accordance with a first alternative embodiment of theinvention;

FIG. 18 illustrates a side view of the collet in accordance with thefirst alternative embodiment of the invention;

FIG. 19 illustrates a proximal end view of the collet of FIG. 18;

FIG. 20 illustrates a sectional side view of the sleeve in accordancewith the first alternative embodiment of the invention;

FIG. 21 illustrates a top plan view of the clamp tube of the firstalternative embodiment of the invention;

FIG. 22 illustrates a top plan view of the clamp tube snap of the firstalternative embodiment of the invention;

FIG. 23 illustrates a side view of the channel adapter of the firstalternative embodiment of the invention;

FIG. 24 illustrates a sectional side view of a handle and frame portionin accordance with the first alternative embodiment;

FIG. 25A illustrates a sectional view of the frame in accordance withthe first alternative embodiment;

FIG. 25B illustrates a distal end view of the frame half illustrated inFIG. 25A;

FIGS. 26A and 26B illustrate side and distal end views, respectively, ofthe inner handle of the first alternative embodiment;

FIGS. 27A, 27B, 27C, 27D and 27E illustrate bottom plan, front side,sectional front side and two partial rear side views, respectively, ofthe frame clamp tube;

FIGS. 28A and 28B illustrate top and front views, respectively, of aframe leaf spring;

FIG. 29 illustrates a sectional side view of the outer tube of the firstalternative embodiment;

FIGS. 30A and 30B illustrate side and distal end views, respectively, ofthe outer handle of the first alternative embodiment;

FIG. 31 illustrates a side view of a drive tube in accordance with thefirst alternative embodiment;

FIGS. 32A and 32B are top plan views of the frame clamp tube, drive tubeand leaf spring illustrating proximal and distal frame clamp tubepositions;

FIG. 33 illustrates a perspective cutaway view of an assembled staplerapparatus in accordance with a second alternative embodiment of theinvention;

FIGS. 34 and 34A illustrate an exploded perspective view of the frameand actuating assembly of the stapler apparatus in accordance with thesecond alternative embodiment of the invention;

FIGS. 35 and 35A illustrate an exploded perspective view of elements ofthe tube assembly of the stapler apparatus in accordance with the secondalternative embodiment of the invention;

FIGS. 36 and 37 illustrate side and top views of the extension tube;

FIGS. 38-40 illustrate a side view in partial cross section, partial topview, and frontal view, respectively, of the rack rod;

FIGS. 41-43 illustrate top and side views of the support structure;

FIGS. 44 and 45 illustrate a top view and a side view in cross-sectionof the collar tube;

FIG. 45A shows an end view in cross-section of the collar tube;

FIGS. 46-49 illustrate top and side cross-sectional views of the upperand lower half of the cover tube;

FIGS. 50-53 illustrate side, bottom and cross-sectional views of thechannel of the stapler apparatus in accordance with the secondalternative embodiment of the invention;

FIGS. 54-56 illustrate top, bottom and side views of the anvil;

FIGS. 57 and 57A illustrate an exploded perspective and assembledperspective views of the cartridge assembly;

FIGS. 58-61 illustrate top, side and frontal views of the cam baradapter;

FIGS. 62-64 illustrate side and top views of the cartridge housing;

FIGS. 65-67 illustrate top, bottom and side views of an anvil member inaccordance with an alternate embodiment of the present invention for usein ligating tubular tissue;

FIGS. 68-69 illustrate an exploded perspective and assembled perspectiveview of a cartridge assembly in accordance with an alternate embodimentof the present invention for use in ligating tubular tissue;

FIGS. 70 and 71 illustrate a side view of clamping jaws in accordancewith an alternate embodiment of the jaw members of the presentinvention; and

FIGS. 72 and 73 illustrate a side view of gripping jaws in accordancewith an alternate embodiment of the jaw member.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The surgical apparatus described herein includes a frame and handleportion supporting an endoscopic portion, i.e., an extended tube-likeportion having a relatively narrow diameter, on the order of about 10millimeters, for insertion into a small opening in or tube inserted intothe body, such as in the abdominal cavity. The endoscopic portiondefines a longitudinal axis and has a length appropriate for reachingthe operation site in the interior of the body. The apparatus may beused in conjunction with endoscopes (devices for visually examining theinterior of the body, for example, by means of fiber optics). Theendoscopic portion of the apparatus is inserted through the smallopening or wound, manipulated to the operation site, and the instrumentis actuated. The endoscopic portion has a fastening and cutting portionincluding an elongated housing which carries a fastening and cuttingportion including an elongated housing which carries a fastening andcutting portion to the operation site. The fastening and cutting portionincludes jaws defined by a staple carrying cartridge (typically locatedat the distal end of the housing), an anvil and further includes aknife. Actuating the operating portion must be accomplished viaintermediate components disposed on or within a narrow longitudinallyextending tubular structure. The bulk of the primary operatingcomponents are housed on or within a frame, which is located outside thehuman (or animal) body being operated upon.

The instrument of the present invention has three basic actions orfunctions.

First, the endoscopic portion is introduced into the body and positionedwith the jaws aligned at the stapling site to receive the target tissue.This may involve rotation of the endoscopic portion relative to thebody, either by rotating the stapling instrument, as a whole, byrotating the endoscopic portion relative to the frame as permitted inthe preferred embodiments, or a combination of both actions.

Second, the instrument has a means for securing the target body tissuebetween the cartridge assembly and the anvil. This is accomplished by aclamping action. With the target tissue clamped between the anvil andthe cartridge assembly, a camming means which surrounds the housing andanvil member is employed to close the jaws of the apparatus and clampthe tissue between the anvil and the tissue contacting surface of thecartridge.

The third action is that of applying the staples to the body tissue. Alongitudinally extending channel is employed to deliver longitudinalmotion to pusher cam bars and a tissue cutting knife. The cam barscontact pusher elements which drive the staples through the body tissueagainst the fastener forming or forming surface of the anvil. After theinstrument has been fired, the clamping action of the jaws is releasedand the instrument may be withdrawn from the body. The following detailswill provide an in-depth understanding of the various elements,operations and functions of the present invention.

FIG. 1 shows a cutaway perspective view of the instrument of the presentinvention 100, which generally comprises a frame 102 supporting anendoscopic portion 103, means for actuating the instrument to clamp bodytissue, and means for firing the instrument to drive staples into thebody tissue and form an incision in the tissue between staple rows.

More particularly, referring now to FIGS. 1 and 2, frame 102 has twoparts: a left portion 102L and a right portion 102R. These portions areoptimally fastened together by means of fastening screws 101, althoughrivets, welds or other means of joining the two frame parts may also beused. The left portion 102L has a vertical elongated slot 102A to allowaccess to a thumbwheel 123 (See FIGS. 1 and 4). Frame 102 is elongatedand has an interior surface defining a distal opening 102B, proximalopening 102C, and interior distal cylindrical chamber 102D, an interiorproximal cylindrical chamber 102E, a circumferential thumbwheel mountinggroove 102H, an upper guideway 102F, and a lower guideway 102G. Theframe is of an overall size and shape convenient for being held in thehand.

Referring additionally now to FIG. 3, toggle lever 104 transfers motionto the toggle links discussed below and thereby provides a means toactivate the clamping action of the apparatus in response to manualpressure from the surgeon or other operator of the instrument. Togglelever 104 is an elongated piece having a distal end pivotally mounted inproximity to the distal end of the frame by means of lever pivot pin105, which is disposed through transversely aligned aperture 104B in thedistal end of the toggle lever 104. Toggle lever 104 further has aproximal end pivotally connected to toggle link 107 by means of togglelink pin 106 which is disposed through aperture 104A in the togglelever. In response to pressure, the toggle lever 104 rotates around theaxis defined by toggle lever pin 105, and transfers movement to thetoggle links.

Toggle link 107 is an elongated member having a rounded first end withfork member 107A, which defines a longitudinal slot 107C, a transverselyaligned aperture 107B for receiving toggle link pin 108, and a backstopsurface 107D. The rounded second end of toggle link 107 has atransversely aligned aperture 107E for receiving toggle link pin 106.Toggle link 107 transfers movement from the toggle lever to toggle link109.

Toggle link 109 is an elongated relatively thin, flat piece having arounded first end with transversely aligned aperture 109A for receivingpin 110, and a partially rounded second end having transversely alignedaperture 109B for receiving toggle link pin 108, and a rotation limitingmember 109C.

The first end of toggle link 109 is mounted in slot 111A of the collarmoving pivot 111 by means of pin 110 which is disposed through aperture109A. The second end of toggle link 109 is pivotally mounted in slot107C in the fork member 107A of toggle link 107 by means of pin 108.Rotation limiter 109C is a flat angular member projecting proximallyfrom the second end of the toggle link 109. The rotation limiter isadapted to abut the corresponding backstop surface 107D in toggle link107 such that the joint between toggle links 107 and 109 is preventedfrom further bending in the distal direction. The rotation limiter 109Cthus acts as a locking feature, preventing the toggle lever 104 frombeing depressed, and thereby preventing the clamping function to beactuated. When the coupling is bent in the proximal direction, however,the toggle lever 104 can be fully depressed so as to actuate theapparatus by moving collar moving pivot 111.

Collar moving pivot 111 is a substantially rectangular shaped pieceslidably mounted in the upper guideway 102F of the frame 102. Collarmoving pivot has a longitudinal slot 111A and a transversely alignedaperture 111B in proximity to the distal end of the collar provingpivot. The slot 111A is for receiving the first end of toggle link 109,and the aperture 111B is for receiving pin 110 for pivotally mountingsaid toggle link 109. Collar moving pivot 111 has a depending plate111C, which has a relatively wide spacer portion 111E and transverselyaligned aperture 111D for receiving pin 113 (FIG. 4).

Depending portion 111C is mounted in slot 112B of the collar pivotholder 112 (FIG. 4). Pin 113 disposed through aperture 112C in thecollar pivot holder and 111D in the collar moving pivot, links these twopieces. Collar moving pivot 111 provides a means to convert therotational motion of the toggle links to linear movement in thelongitudinal direction.

Referring additionally to FIGS. 4 and 4A, collar pivot holder 112 is asubstantially cylindrical piece which is located below the collar movingpivot 111, and which is slidably mounted in the proximal cylindricalchamber 102E. Collar pivot holder 112 has a distal end with aninternally threaded axial hole 112A, and a proximal end with alongitudinal slot 112B for receiving depending plate 111C of the collarmoving pivot, and transverse aperture 112C adapted to receive pin 113for mounting the depending plate 111C.

Collar pivot holder 112 provides a means to transmit longitudinalmovement from the collar moving pivot to the collar pivot wheel 115,which is connected by means of the collar pivot support 114.

Collar pivot support 114 has a longitudinally projecting threaded boltportion 114A at its proximal end for mounting into the hole 112A of thecollar pivot holder 112. At its distal end, collar pivot support has alongitudinally projecting pin 114B with a circumferential notch 114C forengaging E-ring retainer 116. Pin 114 is disposed through axial aperture115A of the collar pivot wheel 115, and the distal end of the pin withnotch 114C projects out through the distal end of said aperture 115Awhere E-ring retainer 116 is clipped onto said notch thereby maintainingcollar pivot wheel 115 on pin 114B. Collar pivot support 114 not onlyprovides a means for connecting collar pivot wheel 115 and collar pivotholder 112 so that longitudinal motion may be transferred, but alsoprovides an axis (pin 114B) around which collar pivot wheel 115 mayfreely rotate.

Collar pivot wheel 115 is a substantially cylindrical piece slidablymounted in the proximal cylindrical chamber 102E of body 102. Concentricaperture 115A extends from the proximal to distal end of said collarpivot wheel for receiving pin 114B. Collar pivot wheel 115 further haseccentric hole 115B in its distal end for receiving mounting bolt 125Aof the collar shaft 125 (FIG. 6). Collar pivot wheel 115 is movable bothlongitudinally within proximal cylindrical chamber 102E, androtationally around pin 114B. Collar pivot wheel 115 transferslongitudinal motion to the collar shaft 125 for the purpose of clampingthe jaws of the apparatus.

Channel pin holder 121 is a substantially cylindrical shaped pieceslidably mounted in the distal cylindrical chamber 102D, and having ahollow axial interior. At its distal end, channel pin holder has a malesnap-in plug 121A with contraction slots 121B for mounting into theproximal end of channel pivot 122. Channel pin holder 121 is mountableby means of screws 120 onto firing support shaft 119 and provides ameans for transferring longitudinally movement from the firing supportshaft 119 to the channel pivot for the purpose of firing the surgicalfasteners. Channel pin holder 121 moves only longitudinally. The snap-inplug 121A serves as an axis around which the channel pivot 122 mayrotate.

Firing support shaft 119 is an elongated substantially rectangular pieceslidably mounted in the lower guideway 102G. Concave surface portion119A at the distal end of the firing support shaft 119 is for mountingthe channel pin holder 121, and has a curvature corresponding to theoutside surface of the channel pin holder 121. Screws 120 are disposedthrough transverse apertures 119C in the firing support shaft 119, andinto holes in the bottom of channel pin holder 121 for mounting saidchannel pin holder 121 to the firing support shaft 119. At its proximalend, firing support shaft 119 has a longitudinally extending threadedhole 119B for receiving threaded screw portion 118A of the plunger 118.

Firing support shaft transfers longitudinal movement from the plunger118 to the channel pin holder 121 for firing the fasteners.

Plunger 118 is a rod having threaded screw mounting portions at both thedistal and proximal ends. The distal screw portion 118A is for mountingto the threaded hole 119B in the firing support shaft 119. The proximalscrew portion 118B is for mounting a push button 117 by means of centralthreaded aperture 117A in the push button. The plunger rod extendsproximally outside the proximal opening 102C in the body 102.

Channel pivot 122 is a substantially cylindrical piece located withinthe distal cylindrical chamber 102D of frame 102. At its proximal end,channel pivot 122 has opening 122C to serve as a receptacle for snap-inportion 121A of the collar pin holder 121 upon which the channel pivot122 is rotatably mounted. As can be seen from FIG. 4A, receptacleportion 122C has a circumferential lip 122E to interlock with thesnap-in portion 121A. At its distal end channel pivot 122 has a stud122A for mounting the proximal end of cam bar channel 129 (FIG. 8).Mounting screw 128 is disposed through transverse aperture 122D tosecure the cam bar channel 129. Collar shaft 125 is disposed throughaperture 122B.

Channel pivot 122 provides a means for transferring longitudinalmovement from the channel pin holder 122 to the cam bar channel 129 forthe purpose of firing the surgical fasteners. Channel pivot 122 alsoprovides a means to rotate the cam bar channel 129 and collar shaft 125around the longitudinal axis of the instrument.

Thumbwheel 123 is a disk shaped piece rotatably mounted in acircumferential thumbwheel mounting notch 102H. Thumbwheel 123 has adistally extending cylindrical projection 123B, rectangular slot 123A,detents 123C transverse to slot 123A, projecting distally from thecylindrical projection 123B, and a circumferential surface 123D whichpartially projects through elongated notch 102A. Thumbwheel 123 can berotated by manually applying a turning force to the portion of thecircumferential surface 123D which projects through the elongated notch.Upon being rotated thumbwheel 123 will thereupon turn the cover, cam barchannel, collar shaft, around the longitudinal axis of the instrumentfor the purpose of imparting rotation to the endoscopic portion of theapparatus distal to the frame.

Referring additionally now to FIGS. 5 and 5A, cover 124 is a relativelylong tubular piece having a diameter appropriate for use in endoscopicsurgical procedures and projecting distally through the distal opening102B of the frame in alignment with the longitudinal axis of theinstrument. At its proximal end, cover 124 has a flange 124A which hasnotches 124B to cooperatively engage detents 123C of the thumbwheel 123.Flange 124A is mounted flush against cylindrical projection 123B of thethumbwheel. Cover 124 is rotatably mounted as to turn in conjunctionwith the rotation of the thumbwheel. Collar shaft 125 and cam barchannel 129 extend longitudinally through the interior of the cover 124.Cover 124 provides a means for enclosing the collar shaft 125 and cambar channel 129 to prevent them from contacting extraneous body tissuewhile the instrument is being used.

Referring additionally to FIGS. 6 and 7, collar shaft 125 is arelatively long rod in parallel alignment with the longitudinal axis ofthe instrument and having a proximal end with a threaded screw portion125A for mounting to the collar pivot wheel 115, as discussed above, anda distal end with a screw portion 125B for mounting to the tapped hole126A in collar plug 126. Via collar plug 126, collar shaft 125 transmitslongitudinal motion to the collar 124 for the purpose of closing thejaws of the instrument to secure the target body tissue. Collar shaft125 moves longitudinally, and it may be turned around the instrumentaxis although it does not rotate relative to its own axis.

Collar plug 126 provides a means for connecting collar shaft 125 tocollar 127. Collar plug 126 has a threaded aperture 126A for mountingscrew portion 125B of the collar shaft 125, and distal radialprojections 126 which mount in circumferential slots 127A in the collar127.

Collar 127 is a substantially tubular piece located distally to thecover 124 and aligned with the longitudinal axis of the instrument.Collar 127 has circumferential slots 127A in proximity to the proximalend of the collar 127, and a distal camming edge 127B. As seen in FIG.15A, distal camming edge 127B provides a means for closing the jaws ofthe instrument to secure the target body tissue. This is discussed inmore detail below.

Referring additionally now to FIG. 8, cam bar channel 129 is anelongated piece having an inverted U-shaped cross section and which isslidably mounted in housing 134. At its proximal end, cam bar channel129 has a transverse aperture 129D for receiving fastening screw 128.The proximal end of the cam bar channel 129 is mounted to therectangular mounting stud 122A of channel pivot 122 (FIG. 4). At itsdistal end, cam bar channel 129 has a gripping fork 129B and slot 129A.Gripping fork 129B and slot 129A provide a means of engaging and holdingcam bar adapter 130. Longitudinal notches 129C allow the cam bar channelto move without interference from anvil pivot pin 135 (FIG. 11), asdiscussed below. Cam bar channel 129 transmits longitudinal motion fromchannel pivot 122 to the cam bars 131 and knife 132 for performing thetissue fastening operation.

Referring to FIGS. 8 and 9, cam bar adapter 130 is mounted to thegripping fork 129B of the cam bar channel 129 and provides a means forholding the cam bars 131 and knife 132. Cam bars 131 are parallelly andlongitudinally aligned. Their proximal ends are mounted in thelongitudinal slots 130A of cam bar adapter 130. Knife 132, parallellyand longitudinally aligned with the cam bars 131, is also mounted to aslot 130A in the cam bar adapter 130. Knife 132 has a cutting edge 132Aon its distal end.

Referring additionally now to FIGS. 10, 11, and 11A housing 134 is anelongated piece which is aligned with the longitudinal axis of theinstrument. Housing 134 has a proximal end mounted to the cylindricalprojection 123B of thumbwheel 123 by means of pin 133 (FIG. 5). At itsdistal end, housing 134 has a relatively wider section 134B for engagingand holding a cartridge assembly 137. Transverse aperture 134C receivesanvil pivot pin 135. Housing 134 also has a longitudinally extendingcenter guide rail 134A around which cam bar channel 129 is slidablymounted.

Anvil member 136 is an elongated piece which is pivotally mounted to thehousing 134. At its distal end anvil member 136 has an anvil plate 136Awith a tissue contacting surface 136E with staple forming depressions136D (see FIG. 13). Anvil member 136 comprises arms 136B and, at theproximal end, a hinge 136C for pivotal mounting to housing 134 by meansof anvil pivot pin 135 disposed through the hinge 136C and aperture134C. Anvil member 136 is rotatable between an open position (see FIG.15A) and a closed position (see FIG. 15B) where the anvil formingsurface is brought into close cooperative alignment with the cartridgeassembly 137. Anvil plate 136A also has a longitudinal center groove136F to permit passage of knife 132. Anvil member 136 provides one ofthe jaws of the instrument for clamping and securing the body tissue tothe fastened. Preferably, anvil 136 is provided with one or more tissuestops which engage corresponding depressions, openings or indentationsin housing 134 (see FIG. 17). Tissue stops 454 help preventover-insertion of tissue into the jaws.

Referring additionally now to FIGS. 12, 13 and 14, the cartridgeassembly comprises a cartridge 137 with alignment plate 140, pusherelements or staple drivers 139, and surgical fasteners or staples 138.The staples 138 and pushers 139 are disposed within grooved slots 137Asuch that as the cam bars 131 move distally and longitudinally throughthe cartridge 137, pushers 139 are driven up through the grooved slots137A driving staples 138 through the body tissue layers 201 and 202which are to be joined, and into anvil plate 136A where the legs of thestaples are crimped in staple forming depressions 136D. Alignment plate140 serves as a cover to keep the staple drivers aligned withincartridge 137. Preferably, cartridge 137 contains two rows of staplepusher elements, with each staple pusher element acting on threestaples. One such staple pusher element 139 is illustrated in FIG. 16.The preferred staple drive member there illustrated includes a bodyportion 600 having a distal end 602, a proximal end 604 with at leastone camming surface 606, and three substantially rectangular pusherplates 608, 610, 612 aligned in the direction of cam motion. Pusherplates 608, 610 are laterally aligned on either side of body portion 600and have an end coterminous with the body portion proximal end 604. Themiddle pusher plate 612 has an end coterminous with the body portiondistal end 602. None of the pusher plates extend the full length of thebody portion. Preferably, each pusher plate also includes guide rails614 and a staple cradling notch 616. Guide rails 614 are received by andslide in corresponding slot portions of the cartridge. As shown in FIG.16, each staple drive member is preferably driven by a double cam bar.

A wide variety of staple designs, shapes, sizes and arrangements may beused in the hereinafter described embodiments of the present instrument.For example, the staple pitch, i.e. the midpoint distance betweencorresponding staples, may be varied along with variations in staplelength and the arrangement of the staples in the cartridge 137 in orderto accommodate different applications.

FIG. 14 illustrates the surface of the cartridge 137 which comes incontact with body tissue. Grooved slots 137A terminate in openingsthrough which the staples 138 are ejected. Groove 137B guides themovement of knife 132 through the cartridge.

As will be appreciated from the layout of slots or grooves 137A shown inFIG. 14, the preferred arrangement including two rows of staple drivemember, each acting on three staples, results in six rows of stapleswith three overlapping staggered staple rows on each side of knifegroove 137B. Placing three staggered overlapping rows of staples oneither side of the incision obtains improved tissue holding strength andhemostasis.

A first alternative embodiment of the invention is illustrated in FIGS.17-31. In the embodiment there shown the endoscopic portion 300 of theinstrument is detachable from the frame and handle portion 301 of theinstrument (see FIGS. 17 and 24). Endoscopic portion 300 preferablyconstitutes a disposable unit, the frame and handle portion of theinstrument being reusable with replacement endoscopic portions.

Referring now to FIG. 17, a sectional side view of endoscopic portion300, the endoscopic portion has a housing 324 mounted at the proximalend to a collet 402. At the distal end of the endoscopic portion,housing 324 supports a cartridge housing 334 and an anvil 336. In thisembodiment, a clamping tube 327 has a clamping portion 327A ofsubstantially the same outer diameter as housing 325, a tapered section327B and a shaft portion 327C having a narrow diameter configured anddimensioned to slide axially within housing 324. The proximal end of thenarrow diameter shaft section 327C is fixedly mounted to a clamp tubesnap 404. A cartridge 337 is mounted to cartridge housing 334 andengages cam bars 331 and a knife 332. As shown in FIG. 17, cam bars 331preferably are staggered longitudinally relative to one another in orderto improve the balance of forces generated in driving the preferredthree staple drive members to eject three staggered parallel rows ofstaples on either side of the incision formed by knife 332. Similar tothe first described embodiment, cam bars 331 and knife 332 engage andare supported by a cam bar adapter 330 which, in turn, engages thedistal end of a cam bar channel 329. The proximal end of cam bar channel329 is fixedly mounted to a channel adapter 406.

As shown in FIG. 18, collet 402 is substantially cylindrical in shapehaving a cylindrical support section 408 at the distal end thereof and aplurality of collet fingers 410 extending longitudinally in the proximaldirection. Each collet finger 410 has an outwardly projecting midsectionportion 412 with an inclined surface 414 projecting axially inward inthe proximal direction. Each collet finger also has an outwardlyprojecting proximal flange portion 416 terminating at an inclinedsurface 418 extending axially inward in the proximal direction.

FIG. 19 is a proximal end view of collet 402, illustrating six colletfingers 410 configured as sections of a cylinder. Collet 402 and, morespecifically, collet fingers 410 are preferably made of plastic and maybe flexed inwardly from their normal, or rest position. Fingers 410 havememory and return to their rest position when the flexing force isreleased.

The inner diameter of cylindrical support section 408 is configured toaccept the proximal end of housing 324. The proximal end of housing 324is fixed to cylindrical support section 408 by any appropriate means,including but not limited to friction fit and/or engagement of one ormore projections or ribs 420 on the inner surface of cylindrical supportsection 408 (see FIG. 19) with corresponding openings or slots on thehousing 324.

Referring again to FIG. 17, collet 402 is disposed within and engages anouter sleeve 422 such that sleeve 422 is rotationally immovable relativeto the collet but is longitudinally movable relative to the collet witha limited range of motion. As shown more particularly in FIG. 20, sleeve422 has an outer gripping surface including a gripping ring 424. Sleeve422 has a distal portion 426 including an inwardly extendinglongitudinal rib 428 which engages a longitudinal slot 430 on the outersurface of the collet cylindrical support section 408 (see FIG. 19). Aswill be apparent, engagement of rib 428 and slot 430 prevents rotationalmovement of the sleeve 422 relative to the collet and vice versa. Sleeve422 also has an inwardly projecting flange 432 at the sleeve midsection.Flange 432 has an area 434 of minimum diameter which corresponds to andengages the outer diameter surface of collet fingers 408 betweenoutwardly projecting flanges 412, 416 (see FIG. 17). Flange 432 also hasan inclined surface 436 projecting axially inward in the proximaldirection. Inclined surface 436 substantially corresponds to and engagesinclined surface 414 on collet fingers 410 (see FIGS. 17 and 18). Inorder to limit the range of longitudinal motion of sleeve 422 relativeto collet 402, proximal and distal limiting stops 438, 440 are provided.Proximal limiting stop 438 engages the distal flat surface of theoutwardly projecting midsection 412 of one or more collet fingers 410,thereby limiting longitudinal motion of the sleeve in the proximaldirection. Distal limiting stop 440 abuts the proximal flat surface ofcollet cylindrical support section 408, thereby limiting thelongitudinal motion of the sleeve in the distal direction.

Between these two extreme positions, limited longitudinal motion of thesleeve in the distal direction from the position illustrated in FIG. 17is permitted, such that inclined surfaces 414,436 exert axially inwardforce on collet fingers 410. In this manner, collet fingers 410 and,more particularly, the proximal ends of collet fingers 410, may beflexed inwardly from their rest or memory position for reasons to bediscussed hereinafter.

The proximal section 442 of sleeve 422 has an inner diameter which isconfigured and dimensioned to accept and surround a corresponding outertube projection on the frame with unencumbered rotational motion betweenthe sleeve and the frame.

Referring again to FIG. 17, radial housing support pins 444 extendthrough the cylindrical interior of housing 324 near the distal endthereof. Pins 444 extend through longitudinal slots 446 on clamping tube327 (see FIG. 21) and a similar slot in channel 329 (not shown). Theproximal end of cartridge housing 334 is fixedly mounted to housing 324by housing support pins 444. At the distal end, cartridge housing 334supports cartridge 337. Housing support pins 444 also affix the proximalend of an anvil leaf spring 448 to housing 324. The distal end of spring448 supports anvil 336. As shown in FIG. 17, anvil spring 448 acts as aleaf spring to bias the anvil into the open position there shown.

Preferably, at least one pair of corresponding anvil alignment guides,shown as alignment pin and slot 450, 452 are provided on the anvil andcartridge. Alignment guides 450, 452 ensure proper alignment of theanvil and cartridge tissue contacting surfaces so that staples ejectedfrom the cartridge accurately engage corresponding staple forminggrooves in the anvil. Also preferred are one or more tissue stops 454 toensure proper placement of the body tissue between the jaws withoutover-insertion of the tissue beyond the tissue contacting surfaces ofthe anvil and cartridge.

Clamp tube 327 surrounds the proximal portion of the anvil, anvil springand cartridge housing in a manner similar to the first describedembodiment, and moves longitudinally between the open position shown inFIG. 17 to a distal, closed position clamping the upper jaw closedagainst the lower jaw (see FIGS. 15A and 15B). In the latter positionbody tissue is clamped between the anvil and cartridge in the mannerillustrated in FIG. 13.

As shown in FIGS. 17 and 21, clamp tube 327 has a clamping portion 327Awith an outer diameter substantially the same as housing 324. At theproximal end of clamping portion 327A clamp tube 327 has a taperedsection 327B which joins clamping portion 327A to narrow diameter shaftportion 327C. Clamping portion 327A and shaft potion 327C aresubstantially cylindrical. Shaft portion 327C has an outer diametersmaller than the inner diameter of cylindrical housing 324, therebypermitting longitudinal movement of the clamping tube relative to thehousing. As shown in FIG. 21, shaft portion 327C includes longitudinalslots 446, 456. As previously described, housing support pins 444 extendthrough slots 446. It will be noted that slots 446 are configured topermit sufficient longitudinal movement of clamp tube 327 and channel329 relative to housing 324 to close the instrument jaws and fire theinstrument. Pins 444 isolate the anvil and cartridge housing assembliesrelative to housing 324, and prevent longitudinal or rotational movementof the anvil or cartridge assemblies relative to the housing. Pins 444also prevent rotational movement of the collar tube or channel relativeto housing 324.

The proximal end of clamp tube 327 is connected to the distal end ofclamp tube snap 404 (see FIGS. 17 and 22). As shown in FIG. 22, clamptube snap 404 includes two distal legs 458 which extend into theproximal end of clamp tube 324. Outwardly extending pins 460 isolateclamp tube 324 and clamp tube snap 404 relative to one another. Clamptube snap 404 further includes a substantially cylindrical midsection462 and clamp snap fingers 564. It will further be appreciated thatinward deflection of collet fingers 410 by distal movement of sleeve 422also inwardly deflects clamp snap fingers 464 from their rest positionin FIG. 17.

Channel 329 is disposed within clamp tube 327 and is longitudinallymovable therein for imparting longitudinal motion to cams 331 and knife332. Referring to FIGS. 17 and 23, the proximal end of channel 329 isfixed to the distal end of channel adaptor 406, such as by tabs 466 onchannel adaptor 406 engaging corresponding slots on channel 329 (notshown). The shaft of channel adaptor 406 extends longitudinally throughthe center of clamp tube snap 404 and terminates with a female snap-inreceptor defined by prongs 468.

The preferred frame for this embodiment is shown in FIGS. 24-31.

As shown in FIGS. 24, 25A and 25B, the frame and handle assembly in thisembodiment is configured with a double handle. In this embodiment, innerhandle 470 controls the tissue clamping action of the instrument jaws,and outer handle 472 controls firing of the instrument. Frame 474, whichmay be molded and/or machined in whole or in part, is substantiallyrectangular with a closed proximal end 478, a lower gripping surface 480and an upper, handle receiving surface 482. An opening 484 is providedto receive handles 470, 472 mounted to hinge pin 486. Handles 470, 472may be biased in the open position, illustrated in FIG. 24, as by springloading. The distal portion of opening 484 is defined by an upwardlyextending lip 488. The lower surface of the frame includes a protrudingbulbous region 490 distal to gripping surface 480. As explained ingreater detail below, bulbous region 490 defines an interior cavity 492sufficient to permit arcuate travel of the handles. The distal end offrame 474 terminates at a substantially flat surface having a distalopening 498 (see FIG. 25B). Preferably, frame 474 is cast and/ormachined in two left and right halves fastened together by screws orrivets 496, 497, 499. Each frame half includes a distal inwardlyprojecting flange 500 and a longitudinal rib 502 which define distalopening 498 (see FIG. 25B). Inwardly projecting flange 500, inconjunction with the exterior walls of frame 474 and interior walls 504,define a distal frame chamber 506 to receive and support the proximalend of an outer tube 494.

Referring now to FIGS. 24, 26A and 26B, inner handle 470 includes agripping tab portion 506 at the proximal end of an inner handle arm 508and a lever arm portion 510. A hinge pin aperture 512 is provided at thedistal end of arm 508 to receive hinge pin 486, such that inner handle470 rotates about hinge pin 486 to obtain leveraging mechanicaladvantage at lever arm 510. As shown in FIG. 26B, a distal end view ofthe inner handle, lever arm portion 510 is formed in a substantiallyU-shaped configuration with a pair of lever arm forks 510A, 510B.Referring again to FIG. 26A, each leveraging fork includes and elongatedslot 514 for receiving frame clamp tube pins 516 projecting from eitherside of a frame clamp tube 518 straddled by lever arm fords 510A, 510B.

Frame clamp tube 518 is best described by reference to FIGS. 27A through27E. FIG. 27A is a bottom view of frame clamp tube 518 showing clamptube pins 516 projecting outwardly to either side to engage slots 514 onthe inner handle lever arm portion. An elongated U-shaped slot 524 isprovided for reasons explained later. As shown in FIG. 27B, a front sideview of tube 518, a spring retaining pin 522 is formed and protrudesoutwardly from the frame clamp tube. As shown in FIG. 27C, a sidecross-section view of the frame clamp tube, the distal end of frameclamp tube 518 includes a circumferential recess 526 configured anddimensioned to receive clamp tube snap 564. FIG. 27D is a partial rearside view of the clamp tube showing the proximal end of the clamp tube.As there shown, the rear side of the clamp tube 518 includes a leafspring slot 520 and a leaf spring cam 521. FIG. 27E is a partial rotatedview of tube 518 showing cam 521. As shown, cam 521 is formed by bendinga section of the tube wall to protrude outward from the circumference ofthe tube. Frame clamp tube 518 is longitudinally movable from theproximal position shown in FIG. 24 to a distal position to close theinstrument jaws. The distal end of a clamp tube spring 519 engagesspring retaining pin 522 and the proximal end of clamp tube spring 519engages the screw mount 497. Thus, clamp tube spring 519 retains theframe clamp tube in the proximal position until force is exerted to movethe tube to the distal position. As shown in FIG. 24, the distal end offrame clamp tube 518 is disposed within outer tube 494. In theproximal-clamp tube position there illustrated, the distal end of theframe clamp tube is substantially aligned with the distal end of thecylindrical barrel of outer tube 494.

Referring now to FIGS. 24 and 29, outer tube 494 is substantiallycylindrical and engages the distal opening in frame 474. The proximal,frame engaging portion of outer tube 494 includes an annular flange 534which, together with a distal outer tube body section 536, define anannular groove 537 for receiving inward flange 500 at the distal end offrame 474. Longitudinal ribs 502 on the frame (shown in phantom) engagethe exterior outer tube surface to stabilize outer tube 494 relative toframe 474. Outer tube 494 is fixed relative to frame 474, as bycompression fit and/or locking engagement of one or more correspondingsets of pins and holes, etc. Thus, outer tube 494 projects from thedistal end of frame 474 but is fixed relative to the frame. Theprojecting distal end of outer tube 494 is configured and dimensioned toengage collet 402 on the endoscopic portion of the instrument (see FIG.17). The outer diameter of body section 536 is configured anddimensioned to be inserted into sleeve 422, with collet fingers 410simultaneously urged within outer tube 494 by inwardly inclined rim 538.As shown in FIG. 29, body section 536 includes collet finger recesses540 having slightly inclined distal walls 542. Body section 536 furtherincludes transition walls 544 between the collet finger receivingportion and the cylindrical barrel section 546. Cylindrical barrelsection 546 has a uniform diameter from the proximal termination pointof inclined walls 544 to the proximal end of outer tube 494. As stated,cylindrical barrel section 546 receives frame clamp tube 518 inconcentric longitudinal sliding relation (see FIG. 24). The protrudingdistal portion of outer tube 494 also includes a small bump, protrusionor detent pin 501 for engaging one of detent slots 503 on the innersurface of sleeve 522 (see FIG. 20), such that sleeve 522 may be rotatedbetween distinct detent positions relative to outer tube 494.

Outer handle 472 includes a proximal tab portion 548, a longitudinal armportion 550, and a lever arm portion 552 (see FIGS. 24, 30A and 30B).The proximal end of longitudinal arm portion 552 terminates in tab 548,and the distal end of arm portion 550 includes a hinge pin aperture 554for receiving hinge pin 486 (see FIG. 24).

As shown in FIGS. 30A and 30B, outer handle arm 518 is of substantiallyU-shaped configuration such that inner handle arm 508 may be receivedwithin the open interior of longitudinal arm section 550. Outer handlelever arm portion 552 is configured and dimensioned to have an openinterior section 556 which surrounds the inner handle lever arm portionand clamp tube assembly. Open interior section 556 permits unrestrictedlongitudinal movement of the frame clamp tube in response to innerhandle 470 independent from the action of the outer handle. To obtainopen interior section 556, outer handle lever arm portion 552 includesoutwardly flared regions 558A, 558B, substantially parallel body walls560A, 560B and a neck region 562 terminating at distal end portions 564.Referring to FIG. 30A, each distal end portion 564 includes a sprocketwheel pin receiving aperture 566.

Referring again to FIG. 24, a sprocket wheel 568 is mounted on sprocketwheel pin 566 and engages a chain 570. One end of chain 570 is fixed toframe 474, as by being secured to a pin mount 572. The other end ofchain 570 is fixed to a chain engaging tab 574. Chain engaging tab 574is attached as a downwardly extending tab at the proximal end of a drivetube 576. Drive tube 576 is disposed within frame clamp tube 518 andslides freely relative thereto. As will be appreciated, when outerhandle 472 is closed toward the upper frame surface 482 outer handlelever portion 552 is rotated in the distal direction. This motion causessprocket wheel 568 to follow an arcuate path, within the open bottomregion 592 of the frame, drawing chain 570 and, consequently, drive tube576 in the distal direction. It will be noted that elongated opening 524on the bottom of frame clamp tube 518 accommodates chain 570 to ensurefree movement of the chain and frame clamp tube relative to each other.In addition, a drive tube spring 577 engages frame screw mount 499 and apin (not shown) within drive tube 576 to retain the drive tube in theproximal position shown until the instrument is fired.

Briefly turning to FIG. 31, a side view of drive tube 576, the distalend of drive tube 576 is provided with an axially mounted protrudingstem 578 bearing a push plug 580. Push plug 580 has a chamfered distaltip and is configured and dimensioned to be received between theproximal fingers 468 on channel adaptor 406 (see FIG. 17). As shown inthe sectional portion of FIG. 31, the rear wall of drive tube 576 isprovided with a safety locking slot 579.

Advantageously, a safety locking mechanism is provided in thisembodiment to prevent accidental firing of the instrument. Referring toFIGS. 28A and 28B, a leaf spring 528 is provided having a shank portion529 and a curved tip 530. Curved tip 530 includes curved tip shoulders531 of equal width to shank portion 529 extending approximately half thelength of curved tip 530. Curved tip 530 further includes a centraldrive tube locking tip 533 protruding the full length of curved tip 530.Referring again to FIG. 24, the central region 532 outlined in phantomis a further partial sectional view looking beyond the far wall of drivetube 576. This relationship is better illustrated in FIGS. 32A and 32B,which are top plan views showing the frame clamp tube 518 in proximaland distal positions, respectively, relative to leaf spring 528. Leafspring 528 is mounted to frame 474, as by screw mounting through screwhole 535 (see FIG. 28B), with curved tip 530 extending and biased towardframe clamp tube 518 and drive tube 576. In the proximal positions oftubes 518, 576, drive tube locking pin 533 extends through slot 520 onthe far side of frame clamp tube 518 (see FIGS. 27D and 32A) and engagessafety locking slot 579 on drive tube 576 (shown in phantom in FIG.32A). Thus, in the proximal position, leaf spring 528 and locking pin533 securely lock the drive tube in the proximal position and theinstrument cannot be fired. However, leaf spring shoulder portions 531do not extend into slot 520, but rather ride outside and to either sideof slot 520. As frame clamp tube 518 moves from the proximal to thedistal position, one of shoulder portions 531 rides onto leaf spring cam521, thereby forcing leaf spring 528 away from tubes 518, 576 anddisengaging locking pin 533 from safety locking slot 579 (see FIG. 32B).The leaf spring remains disengaged from the drive tube while the frameclamp tube is in the distal position, and returns to locking engagementwith drive tube 576 whenever frame clamp tube 518 is returned to theproximal position. Advantageously, the force exerted by leaf spring 528against cam 521 also tends to retain frame clamp tube 518 in the distalposition so that the instrument will remain in the clamping position inpreparation for firing. In the position shown in FIG. 32B, frameclamping tube 518 is in the distal position to clamp the instrument jawsclosed, but drive tube 576 remains in the proximal position. However,because safety locking pin 533 is disengaged from slot 579 (shown inphantom), the outer handle may now be closed to move drive tube 576distally to fire the instrument.

In order to assemble the frame and endoscopic portions of the instrumentconstructed in accordance with this embodiment, outer tube 494 isaxially aligned with and inserted into sleeve 522 until collet fingers510, and more specifically annular flanges 416 on the collet fingers,engage collet finger recesses 540. In addition, as outer tube 494 isinserted into sleeve 522, (i) clamp tube snap 564 is inserted into frameclamp tube 518 and mates with corresponding recesses 526 of the frameclamp tube; and (ii) channel adaptor 406 is axially inserted through theframe clamp tube until push plug 580 is seated between channel adaptorfingers 468.

It will be noted that, in this embodiment, endoscopic portion 300 can berotated relative to frame 301 by exerting rotational force on sleeve422. As stated, detent pin 501 and detent slots 503 on the outer tubeand sleeve, respectively, define distinct rotational positions of theendoscope portion relative to the frame. As the endoscopic portionrotates, collet 402 rotates relative to outer tube 494, clamp tube snap564 rotates within frame clamp tube 518, and push plug 580 rotateswithin channel adaptor fingers 468. It will further be noted that in thestarting position of the handles illustrated in FIG. 24, springs 519,577 bias the frame clamp tube and drive tube into their proximalpositions. The related mechanical linkages also urge handles 470, 472into the open positions illustrated. Drive tube locking pin 533 engagesdrive tube safety locking slot 579 to lock the drive tube in theproximal position and, hence, handle 572 in the open position, until theinstrument jaws are clamped closed.

Tissue clamping is effected by closing inner handle 470 against upperframe surface 482. As inner handle 470 pivots about hinge pin 486, pins516 travel in slots 514 to draw frame clamp tube 518 in the distaldirection, overcoming the force of the frame clamp tube spring 519 toadvance frame clamp tube 518 to its distal position. Because frame clamptube 518 engages clamp tube snap 564, movement of frame clamp tube 518imparts longitudinal motion to clamp tube 327, thereby closing anvil 336against the tissue engaging surface of cartridge 337. Moving the frameclamp tube to the distal position also causes leaf spring cam 521 onframe clamp tube 518 to engage and urge leaf spring 528 away from drivetube 576, thereby disengaging drive tube locking pin 533 from safetylocking slot 579.

Thereafter, the instrument may be fired by closing outer handle 472against the inner handle and frame. During this motion, sprocket wheel568, via chain 570, overcomes the force of drive tube spring 577 andimparts distal longitudinal motion to drive tube 576 and, hence, tochannel adaptor 406. Of course, distal longitudinal motion of channeladaptor 406 drives channel 329, cams 331 and knife 332 to eject staplesfrom the cartridge and form and incision between the rows of staplesplaced.

In this embodiment, endoscopic portion 300 may be detached from frameand handle portion 301 by exerting distal force on sleeve 422. Aspreviously stated, during such motion inclined surfaces 414, 436cooperate to flex the collet fingers inward, thereby releasing thecollet from outer tube 494. Collet fingers 410 in turn flex clamp tubesnap 464 to disengage the clamp tube snap from the frame clamp tube.Finally, as sufficient withdrawing force is developed, the distallyinclined surfaces of channel adaptor fingers 468 cause the channeladaptor fingers 468 to release push plug 580, thereby permitting fulldisengagement of the endoscopic portion from the frame. Of course, thewithdrawing force required to release channel adaptor fingers 468 shouldbe sufficiently great that opening outer handle 472 after firing theinstrument does not result in disengagement of the push plug from thechannel adaptor.

Advantageously, the double-handle and safety locking pin arrangement ofthis embodiment prevents accidental firing of the instrument with thejaws in the open position. That is, because the outer firing handle ismounted over the clamping handle and cannot be closed without previouslyand independently closing the inner clamping handle, it is impossible tofire the instrument until the jaws are fully closed to clamp tissue.

A second alternative embodiment of the present invention is illustratedin FIGS. 33-64. In that embodiment the following features are provided.The cartridge assembly deactivates upon firing and is disposable anddetachable from the tube assembly, the anvil assembly positively alignsand interfits with the cartridge assembly, the firing handle is providedwith a manual safety and the clamp handle and firing handle interlock toprevent accidental firings. Each of these features is described ingreater detail below.

Referring now to FIGS. 33, 34 and 34A, frame 600 has two parts, a leftportion 600L and a right portion 600R. These portions are optimallyfastened together by means of ultrasonic welding along the peripheralcontacting surfaces thereof, although screws, adhesives or other meansof joining the two body parts also may be used. The frame 600 is of anoverall size and shape convenient for being held in the hand.

A clamp handle 602 is pivotally mounted within the frame 600 forarticulated movement between an open and a closed position. At a distalend, the clamp handle 602 is provided with a fork portion 604 having atransversely aligned aperture 606 for receiving clamp handle-to-tubepins 608. These pins 608 interfit in slots 610 in the sidewall of theframe 600 for longitudinal reciprocal movement therein. Link pinassembly 612, comprising a pair of links 612a and b interconnected bypin 614, attaches to clamp handle 602 at transverse aperture 616 and toframe 600 wherein pin 614 fits into and is retained by hole 607 in frame600. A tensioned clamp spring 618 and clamp spring pin 620 connectsclamp handle 602 with pin 614 of link pin assembly 612. This spring 618assists in articulated movement of clamp handle 602 between the closedand open positions. Projections 603 on vertical sides of clamp handle602 engage the circumferential edge 605 of frame 600 such that when theclamp handle 602 is pivoted down, it is releasably locked into positionby the engagement of projections 603 and edge 605.

Gear handle assembly 622 includes left and right braced gear handles,624L and 624R respectively, and connecting left and right gear handlepins, 626L and 626R. Left and right braced gear handles 624L and 624Rare mirror images of each other and have a shank portion 628 and a webportion 630. Aperture 632 is formed in each web portion 630 having, onone internal surface of the aperture, an arcuate rack 634.

When assembled, shank portions 628 of left and right braced gearhandles, 624L and 624R, contact in abutting relationship along aninternal surface thereof to form a substantially Y-shaped structure withthe web portions 630 being separated and substantially parallel. Firinghandle 636 is provided with a slot 638 into which shank portions 628 areinserted and held. Transverse apertures 640 are formed in frame portions600L and 600R to receive gear handle pins 626L and 626R respectively.The gear handle assembly is thus pivotal within frame 600 abouttransverse apertures 640.

Gear handle assembly 622 further comprises a gear handle link 642 havingtransverse projections 644 on a distal end thereof. These projections644 are adapted to pivot about transverse bores 646 in the web 630 ofbraced gear handles 624 adjacent arcuate racks 634. Gear handle link 642is further provided with parallel hooked projections 648 on a proximalend which projections are adapted to engage bar 650 on the distal end ofa spring link 652. Transverse projections 654 mounted on the proximalend of spring link 652 interfit with holes 656 formed in the frameportions 600L and 600R. A firing handle return spring 659 is connectedin tension within frame 600 from projection 658 to spring link bar 650to provide a mechanical advantage to return the gear handle assembly toits prefiring position after it has been actuated.

A substantially S-shaped kicker spring 660 is mounted within frame 600and flexes about pin 661. The spring 660 is deflected rearwardly byretracting gear handle assembly 622 and serves to "kick" the assemblyback to the original unretracted position.

A manual safety 662 is provided to lock the firing handle 636 in theunfired position to prevent accidental retraction of the gear handleassembly 622. Safety 662 has transverse projections 664 on a proximalend thereof which projections fit into holes 666 in frame portions 600Land 600R to permit pivotal motion of the safety between an engagedposition and a disengaged position. In the engaged position, a groove668, formed in a distal end of safety 662, frictionally interfits with amating structure 670 on the firing handle 636 to lock the handle in theextended position. To unlock the firing handle 636, the safety 662 issimply pivoted downward out of engagement.

Referring to FIG. 34A, there is shown a pinion spur gear assembly 672comprising a pinion gear 674 interfitting with a spur gear 676 resultingin plural driving surfaces. Pinion gear 674 is further provided withprojections 678 which interfit with holes 680 in frame portions 600L and600R to facilitate rotational motion of the pinion spur gear assembly672 about the transverse axis formed by projections 678.

The driving surface formed by the pitch of pinion gear 674 engagesarcuate rack 634 such that reciprocal motion of gear handle assembly 622serves to rotate the pinion spur gear assembly in both clockwise andcounterclockwise directions. The driving surface formed by the pitch ofspur gear 676 engages a horizontal longitudinal rack 682 formed in theunderside of rack rod 684 (FIGS. 38-40). Rotation of spur gear 676translates through the horizontal longitudinal rack 682, to longitudinalreciprocal motion of the rack rod 684.

Referring now to FIG. 35 there is shown, in exploded view, the tubeassembly of the stapler apparatus in accordance with this secondalternative embodiment of the present invention. At a proximal end, rackrod 684 is longitudinally slidable within frame 600 atop spur gear 676.Rollers 686, rotatable fixed in frame portions 600L and 600R by pins 688engaged in holes 690, abut longitudinal shoulders 692 of the rack rod682 and serve to prevent the rack rod 682 from disengaging from spurgear 676. Further vertical support for the rack rod is provided byinterlock spring 694 (FIG. 34). Interlock spring 694 is formed in asubstantially inverted T-shape and mounted transversely in frame 600with the left and right branches of the "T" fixed into correspondingslots 696 of body portions 600L and 600R. The stalk of the "T" arcsforward to slidably engage a proximal end of horizontal longitudinalrack 682 and maintain a vertical force thereon.

Further, interlock spring 694 serves to assist the unique interlockfeature between the gear handle assembly 622 and the clamp handle 602.Referring collectively to FIGS. 34 and 35, when clamp handle 602 isextended in the open position, the link pin assembly 612 is pivoted suchthat a distal end of links 612a and 612b abut the upper proximal surfaceof rack rod 684 proximate to projection 698. In this position, the linkpin assembly 612 abutting projection 698 prevents distal longitudinalmotion of the rack rod 684. By providing a vertical force proximate theunderside of projection 698, interlock spring 694 prevents the rack rod684 from pivoting downward to disengage the link pin assembly 612.Similarly, when the clamp handle is closed, link pin assembly 612 pivotsabout aperture 607 raising the distal ends of links 612a and 612b aboveprojection 698. Thus it is apparent that the gear handle assembly 622cannot be activated, accidentally or intentionally, when the clamphandle 602 is not closed.

Turning to FIGS. 35 and 38, rack rod 684 is provided with a longitudinalcylindrical shaft 700 having an axially mounted protruding stem 702bearing a push plug 704. Push plug 704 has a chamfered distal tip and isconfigured and dimensioned to be received between the proximal fingers706 on channel 708 (FIG. 50-53).

Channel 708 is an elongated piece having a substantially invertedU-shaped cross-section and which is slidably mounted for reciprocallongitudinal motion. As mentioned above, channel 708 has fingers 706 ata proximal end thereof to receive stem 702. Distal to the fingers 706 isa pair of transverse slots 710 dimensioned and configured to receivepush plug 704. At a distal end of channel 708 there is provided fork 712defining a slot 714 therebetween. Fork 712 has a pair of opposed rampingsurfaces 716 and 718 respectively, the purposes of which will bedescribed in greater detail below. Proximal to fork 712 is abuttingstructure 720 which structure extends below the lowermost dimension offork 712. Biasing spring 722 is positioned on the upper surface ofchannel 708 and may be integrally stamped from the channel structure.This spring 722 imparts a downward force on the channel 708 to helpmaintain its horizontal configuration and to assist in engagement anddisengagement of the channel 708 with cam bar adapter 846.

A clamp tube 724 is provided to interconnect the clamp handle 602 and anextension tube 726. Referring to FIGS. 35 and 35A, clamp tube 724 has alongitudinal bore 728 communicating with a chamber 730. Transverseaperture 732 is formed in a proximal end of the clamp tube 724 andpivotally connects the fork portion 604 of clamping handle 602 by meansof pins 608. Push plug 704 of rack rod 684 passes into the proximal endof chamber 730 and out of the distal end of bore 728 such that fingers706 and slots 710 of channel 708 engage push plug 704 distal to theclamp tube 724.

A flange 734 is formed circumferentially around the periphery of clamptube 724 and is dimensioned to slidably fit within the area defined bythe walls of the tubular portion 736 of frame portions 600L and 600R.Distal to flange 734 of clamp tube 724, a cylindrical section 738 isformed with a locking flange 740 on a distal end thereof. An outer gasseal 742 is positioned around cylindrical section 738 and adhered to thedistal vertical face of flange 734. An inner gas seal 744 is positioneddistal to outer gas seal 742 in sealing contact with shaft 700 of rackrod 684 and adhered to the distal vertical face of locking flange 740.Both inner and outer gas seals are fabricated of a resilientsubstantially gas impermeable foam material such as, for example, aclosed cell polyethylene foam like Volara, by Voltek. Other materials ofconstruction are encompassed by the present invention and are within theknowledge of one skilled in the art.

Outer seal 742 is maintained in sealing relation with respect to frame600 by dimensioning the circumference of the outer seal 742 with theinner circumference of the tubular portion 736 of frame 600. In thisconfiguration, clamping tube 724 may move reciprocally longitudinallywhen driven by the clamp handle 602 while maintaining a substantiallysealing relationship between the outer circumference of cylindricalsection 738, the inner circumference of outer seal 742, the outercircumference of the outer seal 742 and the inner circumference of thetubular portion 736 of frame 600. Similarly, inner gas seal 744maintains a substantially sealing relationship between the outercircumference of shaft 700, inner circumference of inner seal 744, thedistal vertical surface of locking flange 740 and the proximate verticalsurface of inner seal 744.

Referring now to FIGS. 35-37 and specifically to FIGS. 36 and 37 thereis shown extension tube 726 preferably formed as a single tubularstructure so as to provide support to the instrument. A pair oftransverse slots 746 are formed in a proximal end of extension tube 726at a point such that when the extension tube 726 is positioned overcylindrical section 738 of clamp tube 724, transverse slots 746 arepositioned in the area between the flange 734 and the locking flange740. In this position, the proximal end of the extension tube up to thetransverse slot is crimped effectively locking the extension tube 726onto the clamp tube 724 while allowing it to freely rotate. An elongatedlongitudinal aperture 725 is formed in the upper surface of extensiontube 726 at a point near the proximal end thereof. A pair of smallerapertures 727 are provided radially apart from aperture 725 to provideaccess thereto.

At the distal end of extension tube 726 there is provided a pair ofprojections 748 which slope outward from the distal end. Theseprojections 748 engage and interlock with slots 750 formed in theinternal proximal surface of collar tube 752 (see FIGS. 44 and 45). Atits distal end, collar tube 752 is formed with a cross-section havingone set of opposed substantially parallel walls 754 and a top arcuatecamming surface 756. The arcuate camming surface is described in greaterdetail below. One side of collar tube 752 is provided with alongitudinal slot 753 for receiving cartridge releasing structure.

FIGS. 46-49 show the upper and lower cover tube structure whichsurrounds extension tube 726. Upper cover tube half 758 is substantiallysemi-circular in cross-section having a circumferential flange portion760 on a proximal end thereof. Set in from the proximal end is aprojection 762. Extending from the internal surface is a projecting bossstructure 763 which interfits within longitudinal aperture 725 inextension tube 726. This aperture is dimensioned to allow forunrestricted longitudinal motion of extension tube 726.

Lower cover tube half 764 is substantially a mirror image of upper covertube 758 without the boss structure 763 and includes a flange portion766 on a proximal end and projection 768 set in from the end. The distalends of both halfs are chamfered.

Upper and lower cover tube halfs 758 and 764 are joined together,preferably by means of adhesives or ultrasonic welding. Other joiningmethods are also envisaged and are within the skill of those in the art.When joined, the complete circumferential flange made up of upper andlower portions, 760 and 766 respectively, fit into a circumferentialgroove 770 formed in the inner surface of the tubular portion 736 offrame 600. Once in position within groove 770, the cover tube is free torotate about the longitudinal axis relative to the frame 600. The covertube, however, cannot move longitudinally relative to the body 600.

Referring again to FIG. 35, rotation knob 772 is dimensioned to slideover the cover tube structure as shown and interlock with projections762 and 768 at a point distal to the tubular portion 736 of frame 600.The rotation knob 772 is in the form of an abbreviated frustoconicalstructure having a bore 774 therethrough dimensioned to receive thecover tube structure. At a proximal end thereof, knurling 776 may beprovided to facilitate rotation. Because of the interlocking structureof the tubes, rotation of the rotation knob 772 effects rotation of thetube assembly.

A further element of the tube assembly is support 778 (FIGS. 41-43).Support 778 has a central channel portion 780 dimensioned to slidablyreceive channel 708 for longitudinal reciprocal motion therein. Amounting portion 782 is formed at a proximal end and is provided withattaching slots 784 which are fixed to projecting boss structure 763 ofthe upper cover tube half 758. Access to the boss structure 763 toeffect secure attachment of support 778 is provided through apertures727 of the extension tube 726. This configuration allows the support 778to rotate freely with the cover tube while maintaining a fixedlongitudinal position with respect to extension tube 726.

At the distal end of support 778 there is provided a mounting andrelease structure as will be described below. Semi-circular portion 786is tapered at 788 to attach to channel portion 780. Camming surfaces 790are formed in the distal end of semi-circular portion 780. A transverseslot 792 is formed proximal to camming surfaces 790 for receivingprojections 794 of anvil 796. A transverse crimp 798 is made in theupper surface of semi-circular portion 780 to form a transverse strapfor receiving and pivotally holding leaf spring 714 of anvil 796.

Biasing spring 800 is also formed in the upper surface of semi-circularportion 780 and extends inwardly to maintain the channel 708 in thelongitudinal horizontal plane as it passes through support 778.

An L-shaped slot 802 is formed in the side wall of semi-circular portion780 as shown in FIG. 43. This slot 802 forms release catch 804,comprising a rectangular engaging structure 806 having a ramped forwardend 808 and a flexible attaching arm 810 which allows engaging structure806 to be biased inwardly. Release button 812 is positioned on engagingstructure 806 and assists in biasing the flexible attaching arm 810 apredetermined distance inward of the semi-circular portion 780. Whenassembled, semi-circular portion 780 slidably fits within collar tube752 with release button 812 being accessible through longitudinal slot753.

Referring to FIGS. 54-56, anvil 796 is an elongated piece which ispivotally mounted in relation to support 778 by means of leaf spring814. At its distal end, anvil 796 has an anvil plate 816 with a tissuecontacting surface 818 having staple forming depressions 820 (See FIG.54). It its proximal end, anvil 796 is provided with an upper cammingsurface 822 and locking surface 823 which surfaces are engageable withcorresponding top arcuate camming surface 75S. Transverse projections794 are formed at the proximal end of anvil 796 and provide a pivotpoint about which the anvil 796 may be rotated between an open andclosed position by the interaction of camming surface 822, lockingsurface 823 and top arcuate camming surface 75S of collar tube 752.Preferably, the radius of curvature of the top arcuate camming surface756 is shorter than the radius of curvature of camming surface 822 andequal to the radius of curvature of locking surface 823. Thisconfiguration prevents flexing of the camming surface 756 of collar tube752 and lateral movement of the anvil as it is being cammed closed.

Leaf spring 814 is fixed in slot 824 at the proximal end of anvil 796.The annular orientation of the leaf spring 814 is such that, uponinsertion of the anvil 796 into the semi-circular portion 786 of support778, leaf spring 814 passes through the strap formed by transverse crimp798 and maintains anvil 796 oriented in the open position withprojections 794 disposed in transverse slots 792 in the support 778.

Anvil plate 816 also has a longitudinal center groove 824 to permitpassage of a knife 826. Anvil 796 provides one of the jaws of theinstrument for clamping and securing the body tissue to be fastened.Preferably, anvil 796 is provided with one or more tissue stops 828 tohelp prevent over-insertion of tissue into the jaws. In a particularlyadvantageous embodiment shown in FIGS. 55-56 the anvil is provided withfour tissue stops, two of which are disposed on the outer verticalsurface of anvil plate 816 with the remaining two internallytransversely positioned. This unique configuration allows for moreaccurate longitudinal alignment of the jaws and prevents twisting of theanvil upon closure. Anvil 796 is further provided with parallel aligningsurfaces 830 positioned below camming surface 822. These aligningsurfaces are dimensioned to fit within projections 834 on cartridgehousing 832 upon closure of the anvil 796. The engagement of thealigning surfaces 822 and the corresponding projections 834 of cartridgehousing 832 serves to more accurately and securely align anvil 796 andcartridge housing 832 upon closure. Further visual confirmation ofalignment is facilitated by a pair of parallel longitudinal indentations837 formed in the distal end of anvil 796. These indentations 837 allowthe surgeon to view the closed structure of the anvil 796 and cartridgeassembly 836 to confirm accurate longitudinal alignment thereof.

Further, as shown in FIG. 56, the horizontal plane formed by tissuecontacting surface 818 intersects the horizontal plane formed by thecamming portion of the proximal end of anvil 796 at an obtuse angle "α".This angular orientation pre-cambers the anvil 796 and balances theclosure force applied by the anvil 796 to the captured tissue.

As discussed above, a wide variety of staples and fasteners arecontemplated for use with the present apparatus. In a preferredembodiment for use with titanium fasteners, it has been found thatforming of the fasteners in the staple forming depressions 820 isfacilitated by applying a hard, relatively smooth surface on the stapleforming portion of the anvil 796. The preferred method of application ofthis surface is by electroless plating, with the surface being formed ofa metallic alloy such as, for example, nickel, gold, silver, titaniumnitride or chromium. Where nickel is used, the applied surface ispreferably in the range of 100μ-2000μ in thickness with an optimumthickness of between 200μ-500μ. Ranges for other alloys may varydepending upon their inherent characteristics.

Where nickel is to be applied, the preferred method is an electrolessplating method including the steps of: eletrocleaning the anvil in acyanide-containing cleaner, reversing polarity at predeterminedintervals, preferably about every 10-15 seconds, at a current of about50 amps/ft² ; rinsing thoroughly; rinsing in a solution containing astrong acid, preferably 20% HCL, dipping several times; immersing theanvil in a NiCL strike tank for plating, preferably for two to fourminutes at a current of about 50 amps/ft² ; rinsing; and immersing theanvil in an electroless Ni bath, preferably Enthone 418 or 431, for atime sufficient to achieve the desired plating thickness. For example,at a deposition rate of 0.0005 in/hr, a time of between 30 to 40 minuteswould be required to achieve a thickness of about 300μ±50μ. Othercoating procedures are also contemplated including vapor deposition,etc. and are encompassed by the present invention.

Turning now to FIGS. 57-64, there is shown a unique replaceablecartridge assembly 836 in accordance with the present invention. Thecartridge assembly 836 includes: a cartridge housing 832; a cartridge838 having a plurality of pushers 840 and staples 842 disposed inlongitudinal arrangement therein; and a plurality of cam bars 844removably disposed in a cam bar adapter 846 and a knife 826 mounted inthe cam bar adapter 846.

Referring specifically to FIGS. 62-64, the proximal end of cartridgehousing 832 comprises a substantially elongate channel of semi-circularcross-section having a forward and rearward portion 856 and 858respectively. A transverse locking slot 848 is formed in rearwardportion 858 and serves to engage and retain engaging structure 806 ofsupport 778. Upon insertion into collar tube 752, the ramped forward end808 of engaging structure 806 is biased inward by the rearward portion858 of cartridge housing 832 until the engaging structure 806 is totallywithin and retained by locking slot 848.

Rearward projection 850 is formed in the base of cartridge housing 832.The function of this projection 850 will be described in greater detailbelow. Forward of the projection 850 is a bore 852 which receives shearpin 854 formed on cam bar adapter 846. A pair of crimps 862 is providedin opposing sidewalls of the rearward portion of the proximal end of thecartridge housing. These crimps 862 provide a friction fit with cam baradapter 846.

The forward portion 856 of the proximal end of cartridge housing 832 hasprojections 834 which, upon closure of the cartridge assembly 836 andanvil 796, contact and align on anvil aligning surfaces 830 as describedabove. A transverse slot 860 is positioned rearward of projections 834as shown in FIGS. 62 and 64. This slot serves to receive and retainprojections 794 of anvil 796 upon closure of the anvil upon thecartridge assembly 836.

The distal end of the cartridge housing 832 comprises a channelstructure of substantially rectangular cross-section. This distal endconstitutes the cartridge receiving portion and is dimensioned toreceive cartridge 838 therein. Bores 864 and projection 866 serve toengage pins and bores respective in the cartridge 838 so as to align andretain the cartridge 838 within the cartridge receiving portion of thecartridge housing 832.

Referring to FIG. 64, the cartridge receiving portion in the distal endof cartridge housing 832 and the proximal end of cartridge housing 832are joined at an obtuse angle θ defined by the intersection of thehorizontal planes of both the proximal and distal ends of the cartridgehousing 832. This angular orientation serves to pre-camber the cartridgeassembly and facilitates accurate closure and alignment of the jawelements as well as more secure retention of subject tissue.

The cartridge 838 is substantially the same as the cartridge 137described above and includes longitudinal groove structure 868 forreceiving and guiding knife 826 and a plurality of pushers 840 abuttingstaples 842. The staples 842 are advantageously arranged in sixlongitudinal rows with three rows positioned on either side of groovestructure 868.

Two pairs of longitudinal slots 870 formed in the cartridge housing areadapted to receive a pair of double cam bars 844 therein. Each pair ofcam bars serving to drive three corresponding longitudinal rows ofstaples. Further, the two pairs of longitudinal slots 870 extend to theend of cartridge 838 as shown in FIGS. 57 and 57A.

Cam bars 844 are provided with a cam surface 872 in an upper distal endthereof and an overhanging ledge 874 with vertical surface 876 in alower distal end. This overhanging ledge 874 is dimensioned to extendinto the longitudinal slots 870 to a point wherein the vertical surface876 of the overhanging ledge 874 drops down and abuts the forward edge878 of the cartridge retaining portion of the cartridge housing when thecam bars 844 move to their distal fired position. At their proximal end,cam bars 844 are provided with hook structure 880 for releasablyengaging cam bar adapter 846.

Referring now to FIGS. 58-61 there is shown multiple views of the uniquecam bar adapter 846 in accordance with one embodiment of the presentinvention. The cam bar adapter 846 comprises a forward section 882 and arearward section 884. The forward section 882 is substantiallyrectangular in shape and has a central longitudinal groove 886 formedtherein and dimensioned to receive the longitudinal groove structure 868therein when the cam bar adapter is urged to its forwardmost position.Flanges 888 and shelves 890 serve to removably retain the proximal endof cam bars 844.

The rearward section 884 is rectangular in shape with projections 892formed in the proximal end thereof. The rearward section is dimensionedto be receivable within slot 714 of fork 712 in channel 708. Theprojections 892 are dimensioned to engage ramping surface 716 to allowthe fork 712 to ride up and over the projections 892 when the fork 712is moved in the distal direction.

Vertical bore 894 and longitudinal groove 896 are formed in the rearwardsection 884 and serve to retain and hold shank 898 of knife 826. Shearpin 854 is integrally formed with cam bar adapter 845 on a bottomsurface thereof and, in the prefiring position, is aligned with andreceivable into bore 852. Also, in this prefiring position, the rearwardsection 884 of the cam bar adapter 846 is disposed over rearwardprojection 850 to effectively shield engagement of abutting structure720 with projection 850.

FIGS. 65-69 illustrate an embodiment of the cartridge assembly and anvilmember of the present invention which permits tubular structures withinthe body to be ligated and/or divided. Both the cartridge assembly andthe anvil member of this embodiment are clamped and actuated bysubstantially the same frame and tubular structure as that describedabove with respect to the second alternative embodiment and sharesubstantially the same structure as the cartridge and anvil membersshown in other embodiments herein (see FIGS. 12-14, 54-56 and 57) withthe exception of structure located on the distal ends of both the anvilmember and the cartridge assembly.

Referring to FIGS. 65-67, anvil 900 is an elongated piece which ispivotally mounted in relation to support 778 by means of leaf spring902. This leaf spring 902 is fixed in slot 903 at the proximal end ofanvil 900 and, when assembled, is retained in the strap formed bytransverse crimp 798 in support 778. At its proximal end, anvil 900 isprovided with an upper camming surface 904 and a locking surface 906which surfaces are engagable with corresponding top arcuate cammingsurface 756 of collar tube 752. Transverse projections 908 are formed atthe proximal end of anvil 900 and provide a pivot point about which theanvil 900 may be rotated between an open and closed position by theinteraction of camming surface 904, locking surface 906 and top arcuatecamming surface 756 of collar tube 752. As in embodiments previouslydescribed, the radius of curvature of the top arcuate camming surface756 of collar tube 752 is shorter than the radius of curvature ofcamming surface 904 and equal to the radius of curvature of lockingsurface 906.

Anvil 900 also has tissue stops 909 to prevent overinsertion of tissueinto the instrument. Anvil 900 has parallel aligning surfaces 912positioned below camming surface 904. These aligning surfaces aredimensioned to fit within projections 834 on cartridge housing 832 uponclosure of anvil 900.

At its distal end, anvil 900 has an anvil plate 914 with an abbreviatedtissue contacting surface 916 having staple forming depressions 918 andan arcuate tissue capturing portion 920. This tissue capturing portionis advantageously designed in a blunted hook configuration as shown inFIG. 67 in order to assist in the capture and proximation of tubulartissue such as, for example, blood vessels, ducts, etc. withoutunnecessary damage to surrounding tissue. In a particularly preferredembodiment, this arcuate tissue capturing portion is provided withlongitudinal tapered surfaces 922. These surfaces fit within matingsurfaces 924 in the cartridge assembly 910 and serve to provide thesurgeon with a better field of view of the tissue ligation site. Uponclosure, surfaces 922 and 924 also give visual confirmation of correctlongitudinal alignment. Where captured tissue is to be ligated anddivided, a knife 826 is provided and travels in longitudinal groove 928formed in the anvil plate 914.

FIGS. 68 and 69 illustrate a cartridge assembly 910 in accordance withan embodiment of the present invention for use in grasping, ligatingand/or dividing tubular tissue. The cartridge assembly 910 issubstantially similar to the other cartridge assemblies described aboveand includes: a cartridge housing 832; a cartridge 928 having aplurality of pushers 840 and staples 842 disposed in longitudinalarrangement therein; a plurality of cam bars 844 removably disposed in acam bar adapter 846 and, where dividing is to be effected, a knife 826mounted to the cam bar adapter 846.

The proximal end of cartridge assembly 910 is substantially the same asthat described above with respect to cartridge assembly 836 and isengagable with support 778 in substantially the same manner. Similarly,the distal end of cartridge assembly 910 utilizes the same channelstructure of substantially rectangular cross-section.

Cartridge 928 differs somewhat from previous embodiments and includes aplurality of pushers 840 abutting staples 842 arranged in relativelyabbreviated longitudinal rows in a tissue receiving surface 926 ofcartridge 928. Where a knife 826 is to be used to divide captured,ligated tissue, longitudinal groove structure 930 is provided forreceiving and guiding knife 826. In a preferred embodiment, the staples842 are arranged in six longitudinal rows with three rows positioned oneither side of groove structure 930. Bores 932 are provided in the uppersurface of cartridge 928 to receive the innermost tissue stops 908.

For typical tubular structure such as blood vessels and ducts, thetissue receiving surface 926 is abbreviated and utilizes fewer staples842 than previously discussed embodiments. Preferably, the tissuereceiving surface 926 is dimensioned to provide sufficient staples toligate the intended tubular tissue without excess staples being ejectedat the site of the tissue ligation.

Two pairs of longitudinal slots formed in cartridge 928 are adapted toreceive a pair of double cam bars 844 therein. In this embodiment, eachpair of cam bars serves to drive three corresponding longitudinal rowsof staples.

The distal end of cartridge 928 has an anvil mating surface 924 formedtherein to receive arcuate tissue capturing portion 920 of anvil 900when the cartridge assembly and anvil are closed. This mating surfacecomprises an arcuate ramp 936, corresponding in shape to the arcuatetissue capturing portion 920 of the anvil 900, and tapered vertical sidewalls 938, corresponding to tapered surfaces 922 of anvil 900. Thesesurfaces, 920, 936, 938 and 922 engage upon closure to accurately andpositively capture tubular structure for ligating and/or dividing. Theoperation of cam bars 844 and knife 826 is substantially the same asthat described above with respect to FIGS. 57-64.

Further alternative embodiments are contemplated in which all or part ofthe instrument would be disposable. Where the entire instrumentconstitutes a single use, disposable instrument, the endoscopic portionpreferably would be integral with the frame and as much of theinstrument as possible would be constructed of plastic. In othercontemplated embodiments the cartridge, knife and possibly the anvilmight be disposable, alone or as a unit. It is also contemplated, forexample, that a replaceable cartridge assembly could be provided whichincludes the knife and possibly the cam bars.

It is also preferred in all embodiments to include a sealing memberwithin the housing in order to effect an internal seal within thehousing. Of course, such a sealing member must permit longitudinalmovement of the clamping and firing elements.

Suitable materials for use in constructing the instrument in accordancewith the invention include stainless steel, titanium, aluminum andplastic. Where disposability of all or part of the instrument isdesired, plastic is the material of choice for economic reasons. Plasticis also preferred, where possible, in order to minimize the overallweight of the instrument. Of course, certain parts, such as the anvil,have performance requirements which dictate the material used. In thecase of the anvil, the need for high strength and accurately shapeddepressions to deform the staples typically requires use of a metal,such as stainless steel. Similarly, the knife requires a fine cuttingedge and typically is also made from stainless steel. The staples usedwith the present invention may be non-absorbable plastic or metal or anabsorbable synthetic material, such as a copolymer of polyglycolic acid.Of course, the foregoing identification of materials is exemplary only,and numerous variations, substitutions and changes in material willoccur to those of ordinary skill in the art.

OPERATION OF THE INSTRUMENT

In use, the endoscopic portion of the instrument is inserted into thebody, preferably through an endoscopic tube. It is further preferredthat the endoscopic tube apparatus be capable of maintaining a sealedpneumoperitoneum, with the internal sealing member of the housingfurther maintaining this seal despite introduction of the instrument inaccordance with the invention into the endoscopic tube. As a practicalmatter, the jaws of the instrument are closed for insertion into theendoscopic tube, either by pinching the anvil and cartridge prior toinsertion or by closing the clamping mechanism prior to insertion.

After insertion into the endoscopic tube, the endoscopic portion may berotated in order to appropriately orient the instrument at the staplingsite. Rotation of the endoscopic portion relative to the body may beattained by rotating the instrument, as a whole, by rotating theendoscopic portion relative to the frame using finger wheel 123 (seeFIG. 1) or sleeve 522 (see FIG. 17), or rotation knob 772 (see FIG. 33),or any combination thereof.

Referring additionally now to FIGS. 15A and 15B, with the instrumentsproperly oriented so that the tissue to be fastened 201, 202 is disposedbetween the open jaws of the instrument, i.e., between the tissuecontacting surfaces of anvil member 136, 336 and cartridge 137, 337, thejaws are closed to clamp the tissue. In the first embodiment, thesurgeon presses down on toggle lever 104, thereby sliding collar 127distally, via collar shaft 125, collar pivot wheel 115, collar pivotholder 112, and collar moving pivot 111. As collar 127 moves distally inthe direction of arrow A from a first position where the camming edge127B at the distal end of collar 127 is proximal to hinge 136C (FIG.15A), to a second position where the camming surface 127B is distal tothe hinge 136C (FIG. 15B), the camming edge 127B contacts the uppersurface of the anvil arms 136B, thereby forcing anvil member 136 torotate in the direction of arrow B until the fastener forming surface136E is brought into close cooperative alignment with the cartridgeassembly, i.e., the slots 137A are aligned with staple formingdepressions 136D. FIG. 15B illustrates the instrument with the jaws in aclosed position. In the second embodiment described above, the sameresult is obtained by closing inner handle 470 to impart longitudinalmotion to frame clamping tube 518 and clamping tube 337, thereby closeanvil 336 against cartridge 337. It is contemplated that achievingproper instrument placement may require multiple attempts to clamp thetissue prior to firing the instrument.

After closing the instrument jaws, the instrument is ready to be fired.To fire the instrument in the first embodiment, the surgeon presses pushbutton 117, whereby the knife 132 and cam bars 131 are drivenlongitudinally through the cartridge via cam bar channel 129, channelpivot 122, channel pin holder 121, and firing support shaft 117. Asexplained above, as the cam bars 131 are driven longitudinally throughthe cartridge, the staple drive members 139 push staples 138 through thebody tissue against anvil 136, where the staples 138 are crimped. In thesecond described embodiment, outer handle 472 is closed to impartlongitudinal motion to drive tube 576, channel 329, cams 331 and knife332 to fire the staples and make an incision.

Referring to FIGS. 33-35, in use, the endoscopic portion of the secondalternate embodiment of the invention is inserted into the patient,preferably through an endoscopic tube which can safely and effectivelymaintain a sealed relationship with the endoscopic portion of theinstrument. As in the previously discussed embodiments, the jaws of theinstrument are closed for insertion into the endoscopic tube, either bypinching the anvil 796 and cartridge assembly 836 together prior toinsertion or by closing the clamping mechanism prior to insertion.

Once inserted into the body cavity, the anvil 796 and cartridge assembly836 are returned to their first open position (see FIG. 33). Bymanipulating rotation knob 772 and the instrument, the jaws are orientedto capture the object tissue. Tissue stops 828 in anvil 796 serve toprevent overinsertion of the tissue within the jaws. Once the surgeon issatisfied with the placement of the tissue within the jaws, clamp handle602 is pivoted downward until it locks in place within frame 600. Thispivotal motion forces clamp tube 724, extension tube 726, and collartube 752 to move longitudinally distal from frame 600. This distallongitudinal movement causes top arcuate camming surface 756 to cam oncamming surface 822 forcing anvil 796 to pivot such that: projections794 move into transverse slot 860; aligning surfaces 830 fit withinprojections 834; and tissue stops 828 interfit with cartridge assembly836. Similarly, the pivotal motion of the clamp handle 602 serves torotate and disengage the link pin assembly 612 from projection 698 onrack rod 684, freeing the rack rod for actuation by the gear handleassembly 622.

When the surgeon is ready to emplace the staples and cut tissue, manualsafety 662 is disengaged from firing handle 636 and the firing handle isretracted to proximate the frame 600. This retraction causes arcuaterack 734 to impart counterclockwise rotation on pinion spur gearassembly 672. The counterclockwise motion of the pinion spur gearassembly 672 is translated to distal longitudinal motion by horizontalrack 682. Shaft 700, attached to the proximal end of channel 708 isdriven distally causing camming surface 716 of forks 712 to ride up andover projection 892 of the cam bar adapter 845 and drive the cam baradapter in a distal direction. Shear pin 854 is severed and the cam bars844 and knife 826 are driven longitudinally through cartridge 838 tosequentially drive and form staples 842 and cut tissue.

At the distal extreme of the longitudinal stroke, the overhanging ledges874 of cam bars 844 drop over edge 878 of cartridge housing 832 thusabutting vertical surface 876 with edge 878.

After firing, the firing handle 636 is released and returns to itsoriginal position with the help of kicker spring 660 and firing handlereturn spring 659. The return motion of gear handle assembly 622 causesarcuate rack 634 to impart a clockwise rotational motion to the pinionspur gear assembly 672. This clockwise rotational motion is translatedto proximal longitudinal motion of shaft 700 by the horizontal rack 682of rack rod 684. Cam bars 844 are pulled out of cam bar adapter 846 andremain in position in the longitudinal slots 850 of the cartridge 838.The cam bar adapter, with knife 826 attached, moves proximally withincartridge housing 832 until the outer edges of cam bar adapter 846impinge on crimps 862. At that point, forks 712 of channel 708 are clearof biasing spring 800 in support 778.

The cam bar adapter 846 is held in place by crimps 862 while cammingsurface 718 of fork 712 causes the fork to ride up and disengage withprojection 892 of the cam bar adapter. Channel 708 continues to move inthe proximal direction until abutting structure 720 is positionedproximally to rearward projection 850 formed in the floor of cartridgehousing 832. At this point, the entire cartridge assembly 836 isdeactivated.

In the event that the surgeon should accidentally attempt to againretract the firing handle 636 without replacing the deactivatedcartridge with a new unfired cartridge, the resulting distallongitudinal motion of the channel 708 moves abutting structure 720 intocontact with rearward projection 850 effectively preventing furthermovement of forks 712 toward cam bar adapter 846.

After firing, clamp handle 602 is raised with the assistance of clampspring 618 which action retracts clamp tube 724, extension tube 726 andcollar tube 752. This retraction causes leaf spring 814 to move anvil796 out of engagement of transverse slot 860 and pivot anvil 796 upward.Similarly, raising of clamp handle 602 causes link pin assembly 612 toreengage projection 698 on rack rod 684. In this engaged position, therack rod 684 is prevented from moving in the distal longitudinaldirection in response to an attempted retraction of the gear handleassembly 622.

In order to replace the cartridge assembly, the instrument is withdrawnfrom the patient. Release button 812 is depressed, biasing engagingstructure 806 out of transverse locking slot 848. The cartridge assemblyis released and may be removed by pulling it distally out of collar tube752.

To reinsert a new cartridge assembly, the proximal end of the cartridgeassembly is inserted into collar tube 752 until engaging structure 806locks into transverse locking slot 848. The instrument is now ready forreinsertion and continued use.

Operation of the instrument with the ligating and dividing cartridge andanvil assembly shown in FIGS. 65-69 is substantially similar to thatdescribed above. Tubular tissue to be ligated and/or divided is capturedwithin the anvil 900 and the cartridge assembly 910 such that the tissueis transversely oriented distal to tissue stops 908 and proximal fromarcuate tissue capturing portion 920 of anvil 900. The cartridgeassembly 910 and anvil 900 are approximated, effectively interlockingsurfaces 920, 936, 938 and 922. The staples 840 are fired, ligating thetissue and, where desired, knife 826 divides the ligated tissue.Opening, removal and replacement of the deactivated cartridge areeffected in substantially the same way as described above with respectto the second alternative embodiment.

Referring to FIGS. 70-73, it is contemplated that the anvil/cartridgeassembly of the present invention could be replaced with otherinteracting jaw members such as, for example, a pair of gripping jawmembers, 940 and 942 respectively, for holding and dissecting tissue aswell as clamping jaw members, 944 and 946 respectively, for clamping offtissue or portions thereof. These interacting jaw members may includeserrated portions 948 to improve gripping/holding ability.Alternatively, the interacting jaw members may be provided with tissuecontacting surfaces 950 and 952 respectively, which prevent or minimizetrauma to held or clamped tissue.

These interacting jaw members would be mounted in substantially the sameway as the anvil/cartridge assembly described herein with the exceptionthat staples and/or knives need not be driven to join and/or dividetissue.

it will be understood that various modifications can be made to thevarious embodiments of the present invention herein disclosed withoutdeparting from the spirit and scope thereof. For example, various sizesof the instrument are contemplated, as well as various types ofconstruction materials. Also, various modifications may be made in theconfiguration of the parts. For example, in the first embodiment theelongated slot for allowing access to the thumbwheel may be placedalternatively in the left body portion or right body portion. Thereforethe above description should not be construed as limitating theinvention but merely as exemplifications of preferred embodimentsthereof. Those skilled in the art will envision other modificationswithin the scope and spirit of the present invention as defined by theclaims appended hereto.

What is claimed is:
 1. A surgical apparatus comprising:a handle; an elongate shaft connected at a proximal end thereof to said handle and extending distally from said handle, said elongate shaft defining a longitudinal axis and supporting at a distal end thereof a cartridge assembly containing surgical staples and defining a tissue contacting surface having openings through which said surgical staples are ejected, said tissue contacting surface extending parallel to said longitudinal axis of said elongate shaft; an anvil assembly including an elongate anvil body having an anvil surface with a plurality of staple deforming depressions for receiving and forming surgical staples and a spring member extending longitudinally from said elongate anvil body, said anvil assembly adapted to pivotally engage said elongate shaft adjacent the distal end thereof.
 2. The surgical apparatus of claim 1 wherein said spring member is angled relative to said elongate anvil body.
 3. The surgical apparatus of claim 1 further comprising a rotation knob mounted in operative association with said elongate shaft for rotating the cartridge assembly and the anvil assembly relative to the handle section.
 4. The surgical apparatus of claim 1 wherein said openings in the tissue contacting surface of the cartridge assembly are oriented in at least four parallel longitudinal rows.
 5. The surgical apparatus of claim 4 wherein said cartridge assembly further includes a knife mounted for longitudinal motion through the center two of said at least four parallel longitudinal rows.
 6. The surgical apparatus of claim 1 further comprising a camming portion operatively associated with the elongate shaft, said camming portion having a camming surface transverse to said longitudinal axis for contacting a camming surface on said anvil body, said camming portion slidably mounted for movement between a first position in which said transverse camming surface is located proximally to said camming surface of said anvil body and a second position in which said transverse camming surface contacts said camming surface of said anvil body, said camming portion cooperating with said anvil assembly such that when said camming portion is moved from said first position to said second position, said anvil assembly is moved to a closed position relative to the cartridge assembly.
 7. The surgical apparatus of claim 1 further comprising a gas seal mounted in said apparatus for inhibiting the passage of gaseous media through said elongate shaft.
 8. A surgical stapler apparatus comprising:a handle section; an elongate shaft connected at a proximal end thereof to said handle section and extending distally from said handle section, said elongate shaft defining a longitudinal axis and including a movable camming tube having a transverse camming surface and said elongate shaft supporting at a distal end thereof a cartridge assembly containing surgical staples and defining a tissue contacting surface having openings through which said surgical staples are ejected, said tissue contacting surface extending parallel to said longitudinal axis of said elongate shaft; an anvil assembly including an elongate anvil body having a camming surface and an anvil surface with a plurality of staple deforming depressions for receiving and forming surgical staples and a spring member extending longitudinally from said elongate anvil body and angled relative thereto, said anvil assembly having a pair of pivots adjacent the end of said spring member distal to said elongate anvil body for pivotally engaging said elongate shaft adjacent the distal end thereof, said transverse camming surface of said camming tube contacting said anvil camming surface to pivot said anvil assembly relative to said elongate shaft to position said anvil surface opposite said cartridge assembly.
 9. The surgical apparatus of claim 8 further comprising a rotation knob mounted in operative association with said elongate shaft for rotating the cartridge assembly and the anvil assembly relative to the handle section.
 10. The surgical apparatus of claim 8 wherein said openings in the tissue contacting surface of the cartridge assembly are oriented in at least four parallel longitudinal rows.
 11. The surgical apparatus of claim 10 wherein said cartridge assembly further includes a knife mounted for longitudinal motion through the center two of said at least four parallel longitudinal rows.
 12. The surgical apparatus of claim 8, wherein said camming tube is slidably mounted for movement between a first position in which said transverse camming surface is located proximally to said camming surface of said anvil body and a second position in which said transverse camming surface contacts said camming surface of said anvil body, said camming tube cooperating with said anvil assembly such that when said camming portion is moved from said first position to said second position, said anvil assembly is moved to a closed position relative to the cartridge assembly.
 13. The surgical apparatus of claim 8 further comprising a gas seal mounted in said apparatus for inhibiting the passage of gaseous media through said elongate shaft. 